การพัฒนาอุปกรณ์จับยึดเพื่อลดเวลาในกระบวนการกัดยางกันกระแทกคัปปลิ้ง

Abstract

This research aims to develop a jig and fixture to shorten machine setup time in the CNC milling process of rubber coupling components made from polytetrafluoroethylene (PTFE). Due to the high slipperiness and flexibility of the material, conventional manual clamping and positioning resulted in long setup time and high variability. The study applied work and time study techniques, including left–right hand chart analysis, direct time measurement, Westinghouse performance rating, and standard time calculation. The ECRS principle was employed to identify non–value-added activities, particularly in tool setup and workpiece reference positioning. Based on the analysis, a new jig and fixture made from MC Nylon was designed to provide a fixed reference position and minimize reliance on operator skill. After improvement, the number of production steps was reduced from 10 to 9, and the total cycle time declined from 1,151.05 seconds to 956.43 seconds, representing a 16.9% improvement. The non–value-added time of the left hand dropped by 16.3%, while the CNC machining time remained unchanged. The research results indicate that the developed workpiece fixture can effectively shorten machine setup time, improve the consistency of workpiece positioning, and mitigate variability caused by human operations. As a result, the production process becomes more continuous and operates with higher efficiency.